A typical example of a prior art oxygen supplying assembly is shown in U.S. Pat. No. 3,186,407 (a similar disclosure is found in Canadian Pat. No. 751,725). This prior art device meters oxygen from a vessel through an orifice and supplies this oxygen to a face mask by way of a demand valve. The rate of supply of oxygen to the face mask varies substantially with changes in the supply pressure and under many circumstances insufficient oxygen will be supplied to a user in the absence of adequate inhalation by the user. The operational characteristics of the earlier device are not satisfactory and do not meet the requirements of today for the operation of such devices.
Attention is also drawn to U.S. Pat. Nos. 3,547,143, 2,674,829, 2,906,288, 2,819,728, 3,482,591, 2,119,473, 3,538,930, 3,386,458, 3,587,642 and 2,565,560, all of which relate to various aspects of regulators.
It is an object of the present invention to provide a gas dispensing assembly capable of dispensing, on demand, at least six liters per minute of oxygen from a pressurized storage vessel of oxygen with little change in supply rate with changes in the pressure of the oxygen supply as the vessel is emptied.
It is also an object of the present invention to provide a technical and operational advance over the prior art devices such as that disclosed in U.S. Pat. No. 3,186,407 and the other U.S. Patents made of record above.